1. Chemical Solutions Preparations General Biochemistry Laboratory BIOC 201 Rami M. Mosaoa

2. Lecture Outlines Definitions

3. Solution Solute Solvent Concentration All definitions are obtained from Oxford Dictionaries http://www.oxforddictionaries.com/

4. Ways of Expressing Concentration Qualitative Expressions of Concentration:  Diluted Solution  Concentrated Solution Semi-Quantitative Expressions of Concentration:  Unsaturated Solution  Saturated Solution Quantitative Expressions of Concentration:  Percentage (%)  Parts per Million (ppm) & Parts per Billion (ppb)  Molarity (M)  Molality (m) http://www.chem.purdue.edu/gchelp/solutions/character.html

5. Weight to Weight Percent % W/W This unit of concentration is used when the weight of each chemical is used to prepare the solution Weight to weight percent is calculated as the weight of solute divided by the total weight of solution, multiplied by 100% Example: 20g of Sodium Chloride in 100g of solution is 20% by mass solution

6. Volume to Volume Percent %V/V This unit of concentration is used when both chemicals are liquid Volume to volume percent is calculated as the volume of solute divided by the total volume of solution, multiplied by 100% Example: 10 ml of Ethyl Alcohol plus 90 ml of deionized water in a final volume of 100 ml is a 10% by volume solution

7. Weight to Volume Percent % W/V This unit of concentration can be used when a solid chemical is dissolved in a liquid solvent. Weight to volume percent is calculated as the weight of solute divided by the total volume of solution, multiplied by 100% Example: 1 g of phenolphthalein in 100 ml of 95% ethyl alcohol is a 1 w/v % solution

8. Part per Million / Billion (ppm) (ppb) Parts per Million (ppm): is the number of parts of solute per 1 million parts of solution Parts per Billion (ppb): is the number of parts of solute per 1 billion parts of solution Example: 5 ppm Chlorine = 5 g Chlorine in 1,000,000 g of solution.

9. Molarity Molarity is a concentration unit, defined to be the number of moles of solute divided by the number of liters of solution.

10. Molality Molality is a unit of concentration, defined to be equal to the number of moles of solute divided by the number of kilograms of solvent

11. Set up a Prep Room

12. How to Prepare a Solution

13. How to Label